On the go and no time to finish that story right now? Your News is the place for you to save content to read later from any device. Register with us and content you save will appear here so you can access them to read later.

The National Party wants to keep dairy cattle away from all waterways and put $100 million towards retiring farmland next to sensitive waterways for use as environmental buffers.

Party leader John Key made the water quality announcement today at Waituna Lagoon in Southland, alongside environment spokeswoman Amy Adams and primary industries spokesman Nathan Guy.

The fund, over 10 years, would be used to buy and retire selected farmland next to important waterways to protect them from excessive dairying. The land could be used for environmental purposes, or community recreation.

National would also introduce a mandatory requirement to exclude dairy cattle from waterways by July 2017.

"New Zealand's water is among the very best in the world and we want to keep it that way. These are the next steps in our considered and sensible plan to continual improvements in freshwater quality," Ms Adams said.

Earlier this year the Government announced national standards for freshwater, requiring a minimum standard to make rivers safe for wading and boating, and allowing local authorities to set higher standards if they wanted.

The Labour and Green parties want stronger measures to make all lakes and rivers swimmable, and say National's economic blueprint would increase dairying and hurt the environment, which would adversely affect the tourism industry.

National has criticised the Opposition proposals as potentially costing billions.

Ms Adams said the $100 million fund would give councils another option to manage freshwater.

As well as excluding dairy cattle from waterways, National would also work with farmers towards excluding other cattle from waterways over time on intensively-farmed lowland properties.